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91.
Alonso D Skilton G Farina H Delorenzo M Gomez D 《International journal of oncology》1997,10(2):375-379
We examined the effects of the neuropeptide hormones vasopressin and oxytocin, and their respective synthetic derivatives desmopressin and isotocin, on F3II mouse mammary carcinoma cells. Vasopressin and desmopressin at concentrations ranging from 0.1 to 1 mu M were mitogenic for F3II cells and induced protein accumulation. On the contrary, oxytocin and isotocin were moderately growth inhibitory at similar doses. In confluent monolayers vasopressin stimulated the secretion of urokinase, a profibrinolytic enzyme involved in hematogenous metastasis. However, the net effect of the peptide on tumor-derived proteolytic activity was dependent on cell density. Stimulation of cell growth and urokinase production by vasopressin was strongly linked with calcium mobilization. These data suggest that vasopressin and its synthetic analog desmopressin may be important modulators of the behavior of metastatic mammary tumor cells. 相似文献
92.
S. Alonso A. Castro I. Fernandez M. Gömez de Cedrön A. Garcia-Orad E. Meyer M. Martínez de Pancorbo 《International journal of legal medicine》1995,107(5):239-245
The tetrameric STRs, HUMTH01, HUMVWA31A and HUMFES/FPS, were studied in a population from the Basque Country (northern Spain) for their frequency distribution and applicability to identity and paternity testing. All systems conformed to Hardy-Weinberg equilibrium; pairwise comparisons demonstrated the allelic independence between loci, and furthermore, all systems seemed to be in agreement with expectations from the Stepwise Mutation Model (SMM) of the mutation-drift theory, which indicates the homogeneity of the population and suggests a replication slippage mechanism as a possible model for generating alleles. A comparison with other population groups appeared to indicate that frequencies are well conserved in Caucasians, but differ from other racial groups. The calculated parameters a priori probability of exclusion (PEX) and index of discrimination (ID), show the informativeness of these loci for the determination of identity and relatedness of individuals. 相似文献
93.
In addition to the known compounds (+/-)-threo-guaiacylglycerol and the phenethyl alcohols, 3-methoxy-4-dihydroxyphenethyl alcohol and 3,4-dimethoxyphenethyl alcohol, a new irregular phenylpropanoid 2-(3-methoxy-4-hydroxyphenyl)-1,3-propanediol was isolated from the ethanolic extract of the leaves of Apollonias barbujana (Lauraceae). Their structures were elucidated on the basis of spectroscopic methods and chemical transformations. 相似文献
94.
Alonso M Barriuso T Castañeda MJ Díaz-Caneja N Gutiérrez I Sarmiento JJ Villar E 《Health physics》1999,76(4):388-392
A method to estimate the absorbed dose to organs in diagnostic radiology was developed. The method is based on Monte Carlo techniques and has been prepared as a tool that can be adapted to any type of examination or view and which is readily available since it is used in a personal computer and not as a list of numerical results. It has been developed with the EGS4 system for static examinations in diagnostic radiology. A study was made of the absorbed doses to different parts of the head during a conventional x-ray examination. Simulation was performed for different arrangements (monoenergetic beam, spectrum, different number of histories, different size of cells, etc.). The method is capable of estimating doses in agreement with those measured experimentally and those obtained by other authors. 相似文献
95.
A Pusztai G G Bardocz R Alonso M J Chrispeels H E Schroeder L M Tabe T J Higgins 《The Journal of nutrition》1999,129(8):1597-1603
The effect of expression of bean alpha-amylase inhibitor (alpha-AI) transgene on the nutritional value of peas has been evaluated by pair-feeding rats diets containing transgenic or parent peas at 300 and 650 g/kg, respectively, and at 150 g protein/kg diet, supplemented with essential amino acids to target requirements. The results were also compared with the effects of diets containing lactalbumin with or without 0.9 or 2.0 mg bean alpha-AI, levels equivalent to those in transgenic pea diets. When 300 and 650 g peas/kg diet were fed, the daily intake of alpha-AI was 11.5 or 26.3 mg alpha-AI, respectively. At the 300 g/kg level, the nutritional value of the transgenic and parent line peas was not significantly different. The weight gain and tissue weights of rats fed either of the two pea diets were not significantly different from each other or from those of rats given the lactalbumin diet even when this was supplemented with 0.9 g alpha-AI/kg. The digestibilities of protein and dry matter of the pea diets were slightly but significantly lower than those of the lactalbumin diet, probably due to the presence of naturally occurring antinutrients in peas. The nutritional value of diets containing peas at the higher (650 g) inclusion level was less than that of the lactalbumin diet. However, the differences between transgenic and parent pea lines were small, possibly because neither the purified recombinant alpha-AI nor that in transgenic peas inhibited starch digestion in the rat small intestine in vivo to the same extent as did bean alpha-AI. This was the case even though both forms of alpha-AI equally inhibited alpha-amylase in vitro. Thus, this short-term study indicated that transgenic peas expressing bean alpha-AI gene could be used in rat diets at 300 g/kg level without major harmful effects on their growth, metabolism and health, raising the possibility that transgenic peas may also be used at this level in the diet of farm animals. 相似文献
96.
García Vicente A García Del Castillo E Soriano Castrejón A Alonso Farto J 《Revista espanola de medicina nuclear》1999,18(5):367-370
Esthesioneuroblastoma is an uncommon tumor originating in the upper nasal cavity and constitutes 3% of all intranasal neoplasms. Few references exist about the expression of somatostatin receptors in these tumors. Our case demonstrates a good correlation between the somatostatin receptor scintigraphy and magnetic resonance imaging. 相似文献
97.
98.
Influence of early posttraumatic hypothermia therapy on local cerebral blood flow and glucose metabolism after fluid-percussion brain injury 总被引:8,自引:0,他引:8
OBJECT: Using autoradiographic image averaging, the authors recently described prominent foci of marked glucose metabolism-greater-than-blood-flow uncoupling in the acutely traumatized rat brain. Because hypothermia is known to ameliorate injury in this and other injury models, the authors designed the present study to assess the effects of posttraumatic therapeutic hypothermia on the local cerebral metabolic rate of glucose (LCMRglu) and local cerebral blood flow (LCBF) following moderate parasagittal fluid-percussion head injury (FPI) in rats. METHODS: Either cranial hypothermia (30 degrees C) or normothermia (37 degrees C) was induced for 3 hours in matched groups of rats immediately after FPI; LCMRglu and LCBF were assessed 3 hours after concluding these temperature manipulations. In rats subjected to FPI, regardless of whether normothermia or hypothermia ensued, LCBF was reduced relative to the sham-injury groups. In addition, when FPI was followed by hypothermia (FPI-30 degrees C group), the subsequent LCBF was significantly lower (35-38% on average) than in FPI-37 degrees C rats. Statistical mapping of LCBF difference imaging data revealed confluent cortical and subcortical zones of significantly reduced LCBF (largely ipsilateral to the prior injury) in FPI-30 degrees C rats relative to the FPI-37 degrees C group. Local glucose utilization was reduced in both hemispheres of FPI-37 degrees C rats relative to the sham-injury group and was lower in the right (traumatized) hemisphere than in the left. However, LCMRglu values were largely unaffected by temperature manipulation in either the FPI or sham-injury groups. The LCMRglu/LCBF ratio was nearly doubled in FPI-30 degrees C rats relative to the FPI-37 degrees C group, in a diffuse and bihemispheric fashion. Linear regression analysis comparing LCMRglu and LCBF revealed that the FPI-37 degrees C and FPI-30 degrees C data sets were completely nonoverlapping, whereas the two sham-injury data sets were intermixed. CONCLUSIONS: Despite its proven neuroprotective efficacy, early posttraumatic hypothermia (30 degrees C for 3 hours) nonetheless induces a moderate decline in cerebral perfusion without the (anticipated) improvement in cerebral glucose utilization, so that a state of mild metabolism-greater-than-blood-flow dissociation is perpetuated. 相似文献
99.
Alonso R Gnanadicom H Fréchin N Fournier M Le Fur G Soubrié P 《The European journal of neuroscience》1999,11(3):967-974
A remarkable feature of dopamine functioning is that the concomitant activation of D1-like and D2-like receptors acts to intensify the expression of various dopamine-dependent effects, in particular the expression of the immediate-early genes, c-fos and zif268. Using non-peptide neurotensin receptor antagonists, including SR48692, we have determined that blockade of neurotensin receptors reduced the cooperative responses of direct acting D2-like (quinpirole) and partial D1-like (SKF38393) dopamine agonists on the expression of Fos-like antigens and zif268 mRNA. Pretreatment with SR48692 (3 and 10 mg/kg) reduced the number of Fos-like immunoreactive cells produced by the combined administration of SKF38393 (20 mg/kg) and quinpirole (1 mg/kg) in the caudate-putamen, nucleus accumbens, globus pallidus and ventral pallidum. High-affinity neurotensin receptors are likely to be involved in these D1-like/D2-like cooperative responses, as compounds structurally related to SR48692, SR48527 (3 mg/kg) and its (-)antipode, SR49711 (3 mg/kg), exerted a stereospecific antagonism in all selected brain regions. Pretreatment with SR48692 (10 mg/kg) also diminished Fos induction by the indirect dopamine agonist, cocaine (25 mg/kg), particularly at the rostral level of the caudate-putamen. In situ hybridization experiments in the caudate-putamen indicated that SR48692 (10 mg/kg) markedly reduced zif268 mRNA labelling produced by SKF38393 plus quinpirole in cells not expressing enkephalin mRNA, but was unable to affect the concomitant decrease of zif268 mRNA labelling in enkephalin-positive cells. Taken together, the results of the present study indicate that neurotensin is a key element for the occurrence of cooperative responses of D2-like and partial D1-like agonists on immediate-early gene expression. 相似文献
100.
Martín-Marquina Aspiunza A Zudaire Bergera JJ Sánchez Zalabardo D Arocena García-Tapia J Sanz Pérez G Díez-Caballero Alonso F Rosell Costa D Robles García JE Berián Polo JM 《Actas urologicas espa?olas》1999,23(1):5-9
Study of 165 patients with prostate adenocarcinoma who underwent radical prostatectomy using a retropubic approach. Mean PSA is 19 ng/ml, mean age 63 years and median follow-up 26 months. 22 patients (13.2%) reported complications during the first month post-surgery, primarily urinary fistula of more than 5 days long in 5 patients and rectal injury in 3.49 patients (29%) reported complications after the first month, mainly urinary incontinence in 26 cases and stenosis of the urethrovesical juncture in 15. The group with early complications showed no significant differences compared to those who had none, neither in PSA (p = 0.3) or a worse pathological stage (p = 0.1), and no evidence is shown in terms of biochemical progression or in disease free progression (p = 1). Patients with urethrovesical juncture stenosis have higher mean PSA (p = 0.01), greater biochemical progression (p = 0.006), worse Gleason (p = 0.03 = and worse progression free survival (p = 0.01). Patients with stress incontinence showed no differences compared to the other groups relative to the studied factors. 相似文献